Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quantas equipes tiveram Gary Megson como gerente recém-contratado.
 ###Tabelas: CREATE TABLE casualties (casualties_id AUTO_INCREMENT PRIMARY KEY, Year VARCHAR, Security Forces VARCHAR, Insurgents VARCHAR, Civilians VARCHAR, Total: VARCHAR) CREATE TABLE complete_formula_one_world_championship_results (complete_formula_one_world_championship_results_id AUTO_INCREMENT PRIMARY KEY, Year INT, Entrant VARCHAR, Chassis VARCHAR, Engine VARCHAR, Points INT) CREATE TABLE tallest_buildings_under_construction (tallest_buildings_under_construction_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Name VARCHAR, City VARCHAR, Height VARCHAR, Floors INT) CREATE TABLE current_usl_soccer-specific_stadiums (current_usl_soccer-specific_stadiums_id AUTO_INCREMENT PRIMARY KEY, Stadium VARCHAR, Club(s) VARCHAR, Division VARCHAR, City VARCHAR, Capacity INT, Opened VARCHAR) CREATE TABLE managerial_changes (managerial_changes_id AUTO_INCREMENT PRIMARY KEY, Team VARCHAR, Outgoing manager VARCHAR, Manner of departure VARCHAR, Date of vacancy VARCHAR, Incoming manager VARCHAR, Date of appointment VARCHAR, Position in table VARCHAR)  
SELECT COUNT Position in managerial_changes FROM managerial_changes WHERE Incoming manager = Gary Megson